Transit vehicle door systems must meet a number of conflicting requirements. They must operate quickly, to meet the pressures of urban mass transit, and they are subject to a number of safety requirements. One such requirement is that a passenger must not be able to fall out of the transit vehicle when it is in motion. Another requirement is that a passenger who has a body part, or clothing, caught by closing doors must be able to extricate the trapped body part or clothing. On a typical passenger transit train, the doors are not directly observed by the operator of the train.
It is known to provide transit vehicle doors which have resilient means disposed between the door, or doors, and a lock for the door(s) so that if a body part or garment of a passenger is caught by closing door(s), the passenger can force the door(s) open a small amount to a pushback position in order to extract the body part or garment. To do this, the passenger must overcome resilient forces, as well as the weight and friction of the door(s). With these prior art systems, the passenger may not exert enough force to open the door(s) sufficiently to extract the body part or garment. Serious injury or death may result.